From: Vladimir Oltean <vladimir.olt...@nxp.com>
There is one place where we cannot avoid accessing driver data, and that
is 2-step PTP TX timestamping, since the switch wants us to provide a
timestamp request ID through the injection header, which naturally must
come from a sequence number kept by the driver (it is generated by the
.port_txtstamp method prior to the tagger's xmit).
However, since other drivers like dsa_loop do not claim PTP support
anyway, the DSA_SKB_CB(skb)->clone will always be NULL anyway, so if we
move all PTP-related dereferences of struct ocelot and struct ocelot_port
into a separate function, we can effectively ensure that this is dead
code when the ocelot tagger is attached to non-ocelot switches, and the
stateful portion of the tagger is more self-contained.
Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
---
net/dsa/tag_ocelot.c | 32 +++++++++++++++++++++-----------
1 file changed, 21 insertions(+), 11 deletions(-)
diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index 8ce0b26f3520..fe00519229d7 100644
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c
@@ -5,6 +5,25 @@
#include <soc/mscc/ocelot.h>
#include "dsa_priv.h"
+static void ocelot_xmit_ptp(struct dsa_port *dp, void *injection,
+ struct sk_buff *clone)
+{
+ struct ocelot *ocelot = dp->ds->priv;
+ struct ocelot_port *ocelot_port;
+ u64 rew_op;
+
+ ocelot_port = ocelot->ports[dp->index];
+ rew_op = ocelot_port->ptp_cmd;
+
+ /* Retrieve timestamp ID populated inside skb->cb[0] of the
+ * clone by ocelot_port_add_txtstamp_skb
+ */
+ if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
+ rew_op |= clone->cb[0] << 3;
+
+ ocelot_ifh_set_rew_op(injection, rew_op);
+}
+
static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
struct net_device *netdev)
{
@@ -29,17 +48,8 @@ static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
ocelot_ifh_set_qos_class(injection, skb->priority);
/* TX timestamping was requested */
- if (clone) {
- u64 rew_op = ocelot_port->ptp_cmd;
-
- /* Retrieve timestamp ID populated inside skb->cb[0] of the
- * clone by ocelot_port_add_txtstamp_skb
- */
- if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
- rew_op |= clone->cb[0] << 3;
-
- ocelot_ifh_set_rew_op(injection, rew_op);
- }
+ if (clone)
+ ocelot_xmit_ptp(dp, injection, clone);
return skb;
}
--
2.25.1
